The man who gave the founders of Google Earth their big break says New Zealand is addicted to cars, is building too many roads, and needs to get its energy policies under control.

Tim Foresman, a former Nasa scientist and environmental adviser to the United Nations, is here to attend the 'Digital Earth' summit in Wellington.

On Friday, after delivering a lecture to pupils at Auckland's exclusive King's School, Foresman told Fairfax Media NZ that, despite New Zealand's tiny population, it could be the 'Kiwi that roared' and show international leadership on environmental and sustainability issues.

But first, said Foresman, we need a closer look at how we move people and stuff around. He said our car "addiction' ensures 'mass transit is in the Iron Age for New Zealand... you're back there with the Neanderthals in terms of your energy and transportation plans'.

He also believes New Zealand should have chosen a carbon tax rather than a trading system as a way to reduce carbon emissions. Carbon trading meant 'trusting the same people who led us into the Wall St and London debacle'. By contrast, a carbon tax would have been egalitarian and simple.

Foresman was working for the UN Environment Programme when in 2000 he arranged a $50,000 contract with a small startup company called Keyhole, which had created a way to transfer satellite imagery onto a 3D, spinnable, zoomable model of the planet.

At that time, says Foresman, Keyhole was interested in tapping the market for people who wanted to 'look for hotels in Miami', but it soon became apparent that by letting users view the Earth as if from space, the technology was a powerful tool for demonstrating the interconnectedness and fragility of our planet. After that contract - the company's first - it went from strength to strength, and in 2004 it was acquired by tech giant Google and renamed Google Earth.

Foresman said that although businesses such as Google are transforming our daily lives, he fears the company is now so big it could become beholden to its investors, and is starting to struggle with its motto of 'don't be evil'. The problem, he said, is that 'power and money make people act funny'.

But if information technology can be abused, it can also be a huge tool for good, he said. The rise of smartphones and the instant availability of vast quantities of data means consumers are gaining ever more power to force big companies to make sustainable choices.

'If I have the intelligence of technology and instant access with me at all times, I can say 'do I want plastic bag or paper bag?', 'should my baby be on Pampers or diapers?' and I can make my decision with data. And that's where it starts to work.'